The present invention relates to a method for making a relief colored strip.
In particular, a prior art method for making relief colored strips comprises the following operating steps.
At first, is carried out an etching step by using a 20/30 ton eccentric press, on a polypropylene support having a size of 9.5 millimeters and a thickness of 400 microns, or on a polyamide support having the same size.
The eccentric press is provided with a mold holder, supporting a mold having a plurality of inside modular letter-shaped recesses each having a length of 4.5 millimeters and a pointed tip.
The composition of a letter array will define a text to be reproduced by the machine.
Then, the etching pressure is adjusted, and the etching thickness is controlled preferably to 80/90 microns.
The etched material is conveyed to a coloring line, or system, which is conventionally called xe2x80x9cCOLORING MACHINExe2x80x9d.
The strip is caused to pass under a liquid colored resin delivery device, using as a base a colored chlorosulphonated polyethylene, and brought into a solution in a rate of 20% of dry extract, with an aromatic solvent.
Suitable rubbing blades remove on the flat portion of the strip the exceeding ink and the strip is then caused to pass through an infrared oven and is brought to a dry condition.
A rotary brush assembly at the outlet of the oven will fully clean residual materials of the strip, more specifically of the flat portion of the strip.
Then, as an end result, we will have an inked portion in the letter recesses, and a remaining perfectly clear portion.
The colored mass is constituted by:
To 1 Kg of the above base material there are added 500 g of an aromatic solvent.
However, the above disclosed method has the disadvantageous effect that the ink also adheres to undesired portions of the strip being processed.
The aim of the present invention is to provide a method for making a relief colored strip in which the ink material is prevented from adhering to undesired portions of the strip, by using a releasing type of process.
Within the scope of the above mentioned aim, a main object of the present invention is to provide a specifically designed ink having very high anti-abrading strength, as well as a very high anti-aging strength against the atmospheric agents and ultraviolet radiation.
The above mentioned aim and objects, as well as yet other objects are achieved by the present invention which specifically relates to a method for making a colored relief strip comprising a first etching step in which said strip is etched, characterized in that said method further comprises the steps of causing said etched strip to pass through a coloring line and a releasing solution metering unit, provided for metering said solution on said strip etched portion, introducing said strip into a mold provided with a plurality of different cross-section and spacing cavities, and causing the ink to exit said cavities under vacuum and in a properly metered condition, to allow said ink to enter the material recess, conveying the strip through an infrared oven and brushing the strip.